Tester jack



F. J. LINGEL TESTER JACK April 8, 1947.

Filed Dec. 31, 1942 v INVENTOR Patented Apr. 8, 1947 TESTER JACK Frederick J. Lingel, Bluffton, Ohio, assignor to Ray L. Triplctt, Blufiton, Ohio Application December 31, 1942, Serial No. 470,898

6 Claims. 1

The present invention relates to electrical apparatus, more particularly to plug and. jack switches for making and breaking electrical connections in radio circuits, tube and instrument testers.

In testing apparatus of this character, it is necessary to provide a switching arrangement which olfers the greatest facility for rapidly making contact between the circuits, series or shunt, and involves no loss in potential at the contact.

. The primary object of the invention is to provide a tester jack or series of jacks which may be inexpensively constructed and are adapted to control the make and break connections of any number of series or shunt circuits.

Another object is to provide an improved method of assembly and manufacture of a tester jack.

These objects are carried out in brief by provlding a series of jacks arranged in adjacent relation and formed of U-Vshaped elements with projections extending between adjacent jacks in such a way that when a plug connection is made to one of the jacks the circuit through the adjacent jack is also either disconnected or connected as may be desired.

The invention will be better understood when reference is made to the following description andthe accompanying drawings in which::

Figure 1 represents a fragmentary sectional view of a jack switch box which may form part of an, electrical testing apparatus.

Figure2 is a plan view of the switching structure shown in Figure 1, the box or casing having been broken to expose the switch elements.

Figures 3 and 4 are diagrammatic views showing some of the uses of the improved switch.

Figure 5 is a fragmentary sectional view taken.

along line 55 in Figure2.

Figure 6 is a perspective view of the improved jack switch and showing the method of assembly.

Figure 7 illustrates the operation of the switch when the plug is inserted in one of the left hand jack switches shown in Figure 2, while Figure 8 illustrates the operation of the switch when the plug is inserted in one of the right hand jack switches shown in Figure 2.

Referring more particularly to Figures 1, 2 and 6,' reference numeral 1 designates the front panel of a jack switch box, the cover or back portion of which is indicated at 2. The panel is preferably formed of an insulating material, hard rubber, Bakelite, etc., and the enclosing compartment may be made of metal or any other suitable material. The panel I is provided at its rear side (Cl. ZOO-51.10)

2 with a plurality of vertical grooves 3, two as shown, for receiving the jack portionsgcnerally designated at 4 of the respective switches. The latter are positioned along the vertical grooves by means of a plurality of openings 5 which are spaced equidistantly along the vertical grooves. These openings are shouldered as indicated at 6 to receive the head of a hollow rivet I. The inner ends of the rivet l are formed over the flat,

0 the opposite legs 18. The shortened legs 9 are provided with kinks or projections H which extend inwardly toward the longer legslil of the respective jacks. The latter may be made of phosphor bronze or any other suitable spring material and then given a heavy silver or nickel plate.

The right hand group of jacks as seen in Figure 2 is provided with an additional contact 12 which is integrally joined at the flat base portion:

3 to the legs of the right hand group of switches El and It. The extension I2 extends upwardly in the same direction as the legs 9, l0 and is bent into the horizontal direction at a position such as to cause the projection to extend into the space between the legs 9 and ll] of the left hand group of switches. The extensions l2 are so arranged as normally to contact as indicated at l3 the inner surfaces of the short legs 9 of the left hand group of switches. Thus, there is a normal con nection between one leg of the left hand group of switches and the fiat base portion 8 of the right hand group of switches.

The projections or extensions H project inwardly as seen in Figure 1 to a position approxi--- mately the center of the openings in the rivets 1.. These projections take the general shape of a V.

with a rounded apex in order to permit the legs of the switch to be sprung away from one an other when a plug is inserted of the panel. 1,

Electrical connections Mare taken preferably from the outer ends of the longer legs of the switches as is clearly shown on the drawings. These connections may form parts of circuits into the openings which. are involved in one or more testing systems employed forexample in testing the connections of a radio circuit or testing the electrodes of radio tubes, or voltmeters, ammeters, wattmeters etc. The manner in which connections are taken from this apparatus to the improved switch or switches will depend on the purpose of making and breaking the connections at the switches during the testing operation.

The assembly and fabrication of the jack group are illustrated inFigure 5. As shown, the U- shaped leg portions of each jack are inserted in the rectangular grooves 3 with the flat bottom portions 8 resting on the bottom of the grooves. The width of the grooves is such as snugly to receive this fiat bottom portion so that each jack is prevented by the sides of the groove from moving in a rotary or sidewise direction. During assembly the panel portion I is preferably positioned in. a vertical direction. The base portion 8 of each jack is'provided. with an opening for receiving the rivet 1 and each jack is moved along the groove until the opening in the flat jack portion is in register with the opening in the panel I. At this time the rivet I may be inserted into the jack and the inner head thereof peaned over to hold each jack rigidly in place.

. Any suitable form of plug may be employed to make'and' break the circuit connection of the jack. and a typical form has been illustrated in Figures 7 and 8. As shown, the plug is carried on a tubing I5 of insulating material open at one end as indicated at [6 and closed at the other end by a metalplug member H. The inner end orthe plug member is provided with a counterbored opening for receiving the wire i8 of a cable [9, the wire being soldered in position as indicated at 20. The metal plug is provided with two shouldered portions 2|, 22, the latter being of a size as slidably to enter the opening in the rivet I and having a length sufficient to permit the portion 22 to contact with the projection II when the plug is pushed to its innermost position. The shouldered portion 2! has a diametral size somewhat larger than the portion 22 in order toprovide a shoulder which rests against the outer end of the rivet 1, thus limiting the distance that the plug may be inserted into the jack. The arrangement is such that when the plug is inserted into the panel, the portion 22 will cause the short legs 9 to move upwardly so that the normal contact between these legs and the contact portion I: which extends from the adjacent jack is broken at the position l3. Thus the insertion of the plug into any one of the left hand group of jacks as shown in Figure 2 will permit the tip of the plug to make contact with the left hand jack and also to break the contact between this jack and its adjacent jack at the position l3. However, when the plug is inserted into the right hand group of jacks (Figure 2), this plugging action serves to force the lower short legs 9 of these jacks downwardly and the only operation which takes place is that the tip 22 makes contact with the right hand jack, without breaking any contact with the left hand group i jacks as can bereadily seen in Figure 2.

The' structure and arrangement of the jacks aretherefore such that should a pair of plugs 2|; be'connected to opposite sides of an ammeter (Figure 3) and assuming that one of the plugs is inserted in the uppermost right hand jack and the-other plug is inserted in the uppermost left hand jack, the circuit which is normally made between these jacks by the contact member l2 is-now broken at the position it, thus effectively placing the ammeter 23 in series with any circuit which includes the right and left hand jacks. On the other hand, should the plugs be connected to a'volt-meter 24 and the plugs are inserted in two jacks positioned in the same column, right hand or left hand group (Figure 2) the voltmeter will read the voltage of the circuit which includes the two jacks as is indicated in Figure 4.

It is apparent that allkinds of connections, ammeter, voltmeter, testing for ground-and disconnections may be made using the improved type of jack construction by simply selecting the jack or jacks into which the plugs 2| are inserted. An arrangement of this character is especially desirable when testing the connections of radio circuits including the associated radio tubes and also in testing instruments, ammeters, voltmeters, wattmeters, etc., in fact for any use in which a rapid connect and disconnect arrangement is required. J

It is apparent that the contact made between the tip 22 and the respective jacks is such that considerable current may be applied or with drawn from a circuit without appreciable voltage drop or loss of energy. The contacttip' or extension l2 serves the additional purpose of permitting a simplification of the plug structure in that it eliminates the necessity for a ring contact thereon. The plug requires only a tip 22 for performing all of the necessary functions."

It is further evident that my improvedplug and jack structure lends itself readily to being enclosed in a casing 2 which serves to prevent foreign material'from settling on the jack elements. through this case in any suitable and well known manner. 7

Having thus fully described my invention;- what I claim as new and desire to secure by Letters Patent is:

1. Tester jack apparatus comprising a pair of" jacks positioned adjacent one another both oi said jacks being formed of strip material bent; to U-shape, only one of said jacks having a pro jection which extends across the legs of said one jack to a position adjacent one of the legs of the other jack, said cross projection being adapted to connect said two jacks when said first mentioned jack is in use, but to disconnect them when said latter mentioned jack is used.

2. Tester jack apparatus comprising a pair of' jacks positioned adjacent one another both of 7 said jacks being formed of strip material bent to U-shape, only one of said jacks having a pro--;

jection which extends across the legs of said one jack to a position adjacent one of the legs'ofthefl other jack, said projection being normally in contact with said one leg of said other jackand adapted to connect said two jacks when said first' mentioned jack is in use, but to disconnect them,

when said latter mentioned jack is used;

3. Tester jack apparatus comprisinga plurality of jacks arranged in a pair of verticaljparalleli rows, the jacks of each horizontal pair being arranged adjacently edgewise to-one another,

each of said jacks being formed of strip material bent to U-shape, only one of each pair of jacks having a, projection which extends across the legs of said one jack to a position adjacent'one of the" legs of the other jack, said cross projection being The conductors I4 may be taken out'f rows, the jacks of each horizontal pair being arranged adjacently edgewise to one another, each of said jacks being formed of strip material bent to U-shape, only one of each pair of jacks having a projection which extends across the legs of said one jack to a position adjacent one of the legs of the other jack, said projection being normally in contact with said one leg of said other jack and adapted to connect said two jacks when said first mentioned jack is in use, but to disconnect them when said latter mentioned jack is used.

5. Tester jack apparatus comprising a pair of jacks positioned adjacent one another, both of said jacks being formed of strip material bent to a U-shape and having a projection from one leg which extends inwardly toward the opposite leg, an opening in the bottom fiat portion of each U-shaped jack, said opening being adapted to receive a metal plug which contacts with said projection, only one of said jacks havinga member which normally connects said two jacks but disconnects them when a metal plug is inserted in said other jack, said strip material being formed of phosphor bronze plated with silver.

6. Tester jack apparatus comprising a panel provided with a plurality of parallel grooves, said grooves being adapted to receive a plurality of jacks, said jacks being formed of strip material bent to a U-shape and having a width which permits the jacks snugly to fit within said grooves, means including hollow rivets for securing said jacks in the grooves, said hollow rivets being adapted to receive a plug for making connection with the jacks, the jacks of only one groove each having a member which normally connects this one jack with one jack of said other grove but disconnects them when a plug is inserted in the jack of said other groove.

FREDERICK J. LINGEL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 840,537 Weir Jan. 8, 1907 536,809 Jones Apr. 2, 1895 1,401,217 l/Veiss Dec. 27, 1921 1,456,516 Riecken May 29, 1923 1,718,280 Edwards June 25, 1929 2,032,191 Tromp et a1 Feb. 25, 1936 1,586,279 Batchelder May 25, 1926 1,552,189 Austrian Sept. 1, 1925 2,086,424 Koehler July 6, 1937 1,080,563 Knoblock Dec. 9, 1937 215,568 Bunnell May 20, 1879 241,812 McCoy et a1 May 24, 1881 776,326 Hubbell Nov. 29, 1904 vFOREIGN PATENTS Number Country Date 23,706 British 1898 122,885 Swiss Apr. 6, 1927 

